iMac RAM Help Please!!

ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Hi all, First post!

Basically i have a Late 2009 iMac which i recently bought more RAM for, it originally had 2x 2gb chips in it which i have replaced with 2x 4gb Chips and all is good.

Problems start when i try to add 2 more chips, i checked on the apple website and it said my iMac supports up to 16gb RAM so i went out and bought 4x 4gb Chips, Problem is when i put all 4 chips in, my iMac wont start up, it just beeps and the screen stays black. If i take 2 out, then it works with 8gb RAM. Ive tried all kinds of different combinations of different chips in different slots, it only ever works with 2 inserted.

So my question is, am i trying to put more memory than it can handle in there or is there some special sequence, application or upgrade that i need to run in order to upgrade to 16gb?

Thanks in advance for your help.
 

GGJstudios

macrumors Westmere
May 16, 2008
44,427
763
You can find specs on all Apple products, including maximum RAM:
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Thanks for your quick reply but ive already bought the RAM and i know its working in as far as any combination of 2 chips will give me 8gb working.

My question was more, why will my iMac not accept all 4 at the same time? As far as i can see, either something is wrong with 2 of the RAM slots in my iMac or im missing some software update that has to be done to enable 16gb to work?

Thanks
 
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goRoostr

macrumors member
May 17, 2012
63
0
Philadelphia Suburbs
Unplug the power cord from the iMac. Put all 4 chips in, and make sure they're in good. Hold the power button down for at least 10 seconds with the cord unplugged( i usually hold it a little longer to make sure). Plug the power cord back in and turn it on and see what happens. I have had plenty of problems with iMacs being finicky when you change the ram...
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Did what you said, im still getting no screen, it just stays black and the beeping noise only now its also being joined by a loud fan.

Any other ideas?
 
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Jasmynp

macrumors 6502
May 15, 2011
384
78
East Coast, USA
are you sure it's all the way in? You have to use elbow grease to push the chips in. Try to remove them and start fresh being sure everything is lined up and in good.
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
OK Update, ive been playing with it and it seems to be the 2 rear slots on the iMac that are at fault.

I can put any 2 RAM chips in the front 2 slots and they work fine, but if i put 2 in the rear 2 slots, whether there are 2 in the front or not, i get the black screen and beeping. Ive also tried it with just 3 chips inserted to see if its either slot particullarly, but they both give the same result.

Any of you guys seen this before and overcome it or you think its going to have to go to apple for repairs?
 
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forty2j

macrumors 68030
Jul 11, 2008
2,585
2
NJ
I do not believe your RAM is seated, retry the installation process,put your index and middle finger at the edge of the board, if not accessible, someplace for leverage, and push hard with your thumb, you'll feel it seat, it's not difficult, put patience is required;)
^^^

I'm sure the front seats have been "loosened up" by many years of usage, while the rear seats are still virgins.
 
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goRoostr

macrumors member
May 17, 2012
63
0
Philadelphia Suburbs
OK Update, ive been playing with it and it seems to be the 2 rear slots on the iMac that are at fault.

I can put any 2 RAM chips in the front 2 slots and they work fine, but if i put 2 in the rear 2 slots, whether there are 2 in the front or not, i get the black screen and beeping. Ive also tried it with just 3 chips inserted to see if its either slot particullarly, but they both give the same result.

Any of you guys seen this before and overcome it or you think its going to have to go to apple for repairs?
Its very possible your back slots are faulty.. from your original post I interpreted that you said you tried a bunch of different config's and as long as you used 2 chips in any slot it would work, but I guess it wasnt the case. Like everyone else says, try pushing them in as hard as you can.
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Absolutly 100% seated correctly, i took all 4 out to be sure and put them back in, i feel them click in just like the front ones and they are rigid, no movement at all.

Still just a black screen and beeping when the rear slots are used.. Is there a specific order the RAM chips have to be seated and if they are "virgins" as you say is there anything else i can do to break them in?

Sorry for my earlier posts, i thought i had tried the rear slots when i posted it so you didnt misread, what i put was wrong.. sorry about that, ive tried it since then and it now appears to be the front slots that work with any 2 RAM chips in only. really do appreciate your help guys :)
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Ive just had a thought, if the rear RAM slots have never been used could they be disabled by any chance? Would i be able to go into the equivilent of BIOS and check this?

(Not sure what the mac equivilent of BIOS would be, i was a windows only user up until i bought my iMac last year)
 
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MacTech68

macrumors 68020
Mar 16, 2008
2,206
160
Australia, Perth
Just to chime in.

I understand you have tried different configurations, but have you tried specifically:

1. confirm that the two working SO-DIMMS are actually seen as 2 x 4GB (8GB) total memory.

2. Take the two working SO-DIMMs out of the front slots, and replace those with just the two 'suspect' SO-DIMMs in the front slots.

3. Check that the computer sees 2 x 4GB (8GB) total memory.

Secondly, specifically which iMac do you have? Check this link for reference. Check System Profiler. Is it:
'iMac 9,1'
'iMac 10,1'
'iMac 11,1'

There are SMC & EFI firmware updates for some of these.

What CPU speed is and what display size is it?

Can you provide a clear picture of any labeling on the new SO-DIMMs?

Which error tones do you get? See here.

Finally, make sure you aren't snagging the pull tabs on the rear two slots. This might be allowing enough pins of the SO-DIMM to be connected for the iMac to identify the RAM, but fails when testing the RAM on initial power-up, causing the error.
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Just to chime in.

I understand you have tried different configurations, but have you tried specifically:

1. confirm that the two working SO-DIMMS are actually seen as 2 x 4GB (8GB) total memory.

2. Take the two working SO-DIMMs out of the front slots, and replace those with just the two 'suspect' SO-DIMMs in the front slots.

3. Check that the computer sees 2 x 4GB (8GB) total memory.

Secondly, specifically which iMac do you have? Check this link for reference. Check System Profiler. Is it:
'iMac 9,1'
'iMac 10,1'
'iMac 11,1'

There are SMC & EFI firmware updates for some of these.

What CPU speed is and what display size is it?

Can you provide a clear picture of any labeling on the new SO-DIMMs?

Which error tones do you get? See here.

Finally, make sure you aren't snagging the pull tabs on the rear two slots. This might be allowing enough pins of the SO-DIMM to be connected for the iMac to identify the RAM, but fails when testing the RAM on initial power-up, causing the error.
Correct, i have bought 4x 4gb RAM Chips and i can put any 2 of them into the front (Top) RAM Slots and they work, my iMac Boots and shows 8gb 1333 mhz DDR3 RAM in the 'About this Mac' box.

Secondly, my iMac is a intel core 2 duo iMac 10.1 with a 21.5" display, late 2009 model.

Thirdly ive attached a picture i just took of 2 of the chips but i have to apologize, the camera on my phone is abit crap. Not sure which details you need but the label on the front of the chips says "Patriot Memory - PSD34G13332S - PS000792 - 4gb PC3 - 10600 CL9 - RoHS Compliant - PS792-086545".

Lastly, the error tone i get ONLY when the rear slots are used (whether there are 2 chips, 3 chips or all 4) is 1 beep every 5 seconds or so which according to the apple website, means no RAM is detected at all.
 

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MacTech68

macrumors 68020
Mar 16, 2008
2,206
160
Australia, Perth
Correct, i have bought 4x 4gb RAM Chips and i can put any 2 of them into the front (Top) RAM Slots and they work, my iMac Boots and shows 8gb 1333 mhz DDR3 RAM in the 'About this Mac' box.

Secondly, my iMac is a intel core 2 duo iMac 10.1 with a 21.5" display, late 2009 model.

Thirdly ive attached a picture i just took of 2 of the chips but i have to apologize, the camera on my phone is abit crap. Not sure which details you need but the label on the front of the chips says "Patriot Memory - PSD34G13332S - PS000792 - 4gb PC3 - 10600 CL9 - RoHS Compliant - PS792-086545".

Lastly, the error tone i get ONLY when the rear slots are used (whether there are 2 chips, 3 chips or all 4) is 1 beep every 5 seconds or so which according to the apple website, means no RAM is detected at all.
If you bought the RAM directly from Patriot, you may be able to return it. They actually DO have 'Apple specific' memory with different part numbers but (on the face of it) the same specs. The memory you have is a 'generic' version of Patriot RAM. Their product configurator does seem to lack more recent model iMacs, despite other pages listing memory for them.

I assume you've checked the thin plastic pull tabs aren't being fouled in the rear sockets?

EDIT: what happens if you install two SO-DIMMs in the 'suspected' rear slots ONLY?

EDIT2: Also, everything I'm seeing points to this model iMac using PC3-8500 (1066Mhz) RAM, whereas you have PC3-10600 (1333Mhz) RAM. If this is the problem, and I must admit to being a little rusty on backwards compatibility, it appears that you SHOULD INSTEAD have this:

http://www.patriotmemory.com/products/detailp.jsp?prodline=3&catid=34&prodgroupid=79&id=963&type=5
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Yes if i put either 2 of the new 4gb RAM chips or my original 2gb RAM chips into the rear slots and leave the front slots unoccupied i still get the same, no power to screen and a beep sound every 5 seconds or so.

----------

EDIT2: Also, everything I'm seeing points to this model iMac using PC3-8500 (1066Mhz) RAM, whereas you have PC3-10600 (1333Mhz) RAM. If this is the problem, and I must admit to being a little rusty on backwards compatibility, it appears that you SHOULD INSTEAD have this:

http://www.patriotmemory.com/products/detailp.jsp?prodline=3&catid=34&prodgroupid=79&id=963&type=5
How would this only effect the rear slots and allow the front slots to recognise the new RAM?
 
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MacTech68

macrumors 68020
Mar 16, 2008
2,206
160
Australia, Perth
Yes if i put either 2 of the new 4gb RAM chips or my original 2gb RAM chips into the rear slots and leave the front slots unoccupied i still get the same, no power to screen and a beep sound every 5 seconds or so.

----------



How would this only effect the rear slots and allow the front slots to recognise the new RAM?
Given your most recent test, I'd say it doesn't. I'm clutching at straws to say maybe the refresh rate with all 4 fitted may have been a cause due to some kind of interleaving but it now seems not the case.

As goRoostr asks, the final two tests would be:

1. your OLD RAM only in the rear two slots -- which you've done

2. two 4GB in the front and your old RAM in the rear.

I would suggest a strong light and magnifying glass to peer at the rear two slots to see if there is anything blocking them, even a hair or dust.

EDIT: what I DO find strange is that even with two working SO-DIMMs in the front, the machine seems to say "no memory installed" when the rears are fitted.
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Just tried the 2 original 2gb chips in the rear slots with 2x 4gb chips in the front, same result.

It seems to be if absolutly any chip at all is seated in either or both of the rear slots, it just craps itself. Ive tested every chip i have in the front slots so i know their all working.. this has to be the actual slots themselves dosnt it?

Ive also tried it without tucking the black strip back in so i know thats not getting in the way.

Grrrr!!! Thanks for your help guys, the support here has been great but im getting really peaved off with my iMac (not you guys!!) now!

EDIT - Ive decided im going to return this generic RAM and buy some apple specific RAM to see if that makes any difference, ill update you guys in a few days when the new goods arrive!!

Thanks again for your help.
 
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MacTech68

macrumors 68020
Mar 16, 2008
2,206
160
Australia, Perth
Just tried the 2 original 2gb chips in the rear slots with 2x 4gb chips in the front, same result.

It seems to be if absolutly any chip at all is seated in either or both of the rear slots, it just craps itself. Ive tested every chip i have in the front slots so i know their all working.. this has to be the actual slots themselves dosnt it?

Ive also tried it without tucking the black strip back in so i know thats not getting in the way.

Grrrr!!! Thanks for your help guys, the support here has been great but im getting really peaved off with my iMac (not you guys!!) now!
Yes, I feel your pain. I can only further suggest removing ALL external peripherals, removing power for an extended period of time (30 minutes) and then trying again. Sadly it looks like a motherboard fault. Have you tried the 'Apple Hardware Test' (obviously with just the front slots filled) ? Last resorts here.
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Quick update guys, i took the patriot RAM i bought back and bought some new RAM from crucial.com and well, the screenshot attached tells the rest of the story for me :)

Thanks alot for your help with this one guys, i appreciate all the comments and feedback received.
 

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Nandifix

macrumors 6502
May 10, 2012
343
0
Ah, so it was the ram that was faulty. Crucial is always the best in my experience.
 
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ZombieAndy

macrumors newbie
Original poster
May 24, 2012
24
0
Must have been but im still puzzled as to why it would accept 8gb of patriot RAM and then crap itself when i tried 12gb (8gb patriot and the 4gb samsung that was in the iMac to begin with) or 16gb of patriot RAM.

Maybe the speed was too high? Only thing i can think of, but would that make the iMac think it had no RAM in it at all!?
 
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